Platform balance

Abstract

The present disclosure is directed to a platform balance that is suitable for transmitting forces and moments in a plurality of directions. The platform balance is adapted to support a test specimen, such as a large vehicle, in a test environment such as a wind tunnel. The platform balance includes a frame support and at least three spaced-apart transducers coupled to the frame support. Each of the transducers is sensitive about two orthogonal sensed axes. The transducers cooperate to provide signals indicative of forces and moments with respect to at least two orthogonal axes. Each transducer includes a transducer body having a support coupled to a sensor body along an axis of compliance. The sensor body is adapted to deflect about the two orthogonal sensed axes where the sensed axes are mutually orthogonal to the axis of compliance.

1 . A platform balance suitable for transmitting forces and moments in a plurality of directions, the platform balance comprising: 
 a frame support; and    at least three spaced-apart transducers coupled to the frame support, each transducer sensitive about two orthogonal sensed axes wherein the at least three spaced-apart transducers cooperate to provide signals indicative of forces and moments with respect to at least two orthogonal axes.    
   
   
       2 . The platform balance of  claim 1  wherein the frame support includes a first perimeter frame and a second perimeter frame, and wherein the at least three spaced-apart transducers include four spaced-apart transducers coupling the first perimeter frame to the second perimeter frame.  
   
   
       3 . The platform balance of  claim 2  and further comprising a first set of flexures coupled to the first perimeter frame and adapted to engage a ground support, and a second set of flexures coupled to the second perimeter frame and adapted to engage a test specimen.  
   
   
       4 . The platform balance of  claim 3  wherein the second set of flexures are coupled to a belt frame adapted to engage a wheeled test specimen.  
   
   
       5 . The platform balance of  claim 2  wherein each transducer comprises a sensor body coupled to the second perimeter frame and a support coupled to the first perimeter frame, the sensor body being coupled to the support wherein the support is compliant in an axis of compliance, wherein the axis of compliance is orthogonal to a sensed axes of each transducer.  
   
   
       6 . The platform balance of  claim 5  wherein the support comprises two clevis halves disposed on opposite sides of the sensor body along the axis of compliance.  
   
   
       7 . The platform balance of  claim 6  wherein the first perimeter frame is coupled to the two clevis halves.  
   
   
       8 . The platform balance of  claim 5  wherein the support includes a single clevis disposed on a side of the sensor body along the axis of compliance.  
   
   
       9 . The platform balance of  claim 2  wherein the first and second perimeter frames include box beams.  
   
   
       10 . The platform balance of  claim 2  wherein the first and second perimeter frames are nested.  
   
   
       11 . The platform balance of  claim 2  wherein the frame support includes a stiffening frame coupled to the transducers.  
   
   
       12 . The platform balance of  claim 11  wherein the stiffening frame is directly coupled to the first perimeter frame.  
   
   
       13 . A transducer body, comprising: 
 a support; and    a sensor body coupled to the support along an axis of compliance, wherein the sensor body is adapted to deflect about two orthogonal sensed axes, and wherein the sensed axes are mutually orthogonal to the axis of compliance.    
   
   
       14 . The transducer body of  claim 13  wherein the support includes a pair of clevis halves disposed on opposite sides of the sensor body and along the axis of compliance.  
   
   
       15 . The transducer body of  claim 13  wherein the sensor body includes a generally rigid peripheral member disposed about a spaced-apart central hub, wherein at least three flexure members couple the peripheral member to the central hub, and wherein the flexure members are spaced-apart from each other at generally equal angle intervals about the central hub.  
   
   
       16 . The transducer body of  claim 15  wherein the sensor body includes four flexure members.  
   
   
       17 . The transducer body of  claim 15  wherein the central hub is coupled to the support.  
   
   
       18 . The transducer body of  claim 13  wherein the sensor body is adapted to receive a plurality of sensors.  
   
   
       19 . The transducer body of  claim 13  wherein the support includes a compliant member and the transducer body further comprises a second sensor body disposed on a side of the compliant member opposite the first-mentioned sensor body and along the axis of compliance.  
   
   
       20 . A platform balance suitable for use with a test specimen, the platform balance comprising: 
 means for transmitting loads of the test specimen in a plurality of directions; and    means for generating signals indicative of the loads along at least two orthogonal axes by sensing along at least three two orthogonal sensed axes.